Significance: Digital microscopes are becoming an indispensable tool within the pathology lab. Whole-slide microscope scanners are now routinely used to record gigapixel-sized images of surgical pathology specimens for archival, sharing, annotation and automated processing. Unfortunately, whole-slide scanners still cannot efficiently digitize thick specimens, such as fine-needle aspirates (FNAs) and other cytology samples that are commonly used as the first-line modality for diagnosing cancer of the lung, thyroid, pancreas and other sites. Standard microscope lenses can only capture data from a 1 mm2 area per snapshot. Given this limitation, it is currently not technically feasible to fully scan out an entire slide in 3D, which leads to a number of critical bottlenecks within the cytologist's workflow for cancer diagnosis. Proposal: Ramona Optics is developing a new micro-camera array microscope (MCAM) that can overcome these limitations to digitize thick specimens (up to 50 m deep) at 1 m3 volumetric resolution across an entire slide. The resulting multi-gigabyte recording can then be examined by cytopathologists via a custom-developed 3D software interface to aid with various diagnostic tasks. In Phase I of this Fast-Track proposal, Ramona will finalize the hardware and software for its new MCAM-3D device. In Phase II, Ramona will collaborate with the Duke University Medical Center and several other cytopathologists to test and measure MCAM-3D performance on several relevant clinical tasks, including remote telecytology-based assessment of FNA sample adequacy, as well as suitability for secondary diagnosis. Apart from improving workflow and patient care in the hospital, Ramona Optics also expects the MCAM- 3D to enable a number of critical high-throughput imaging experiments in the life sciences that are currently not possible due to the limited throughput of current standard microscope designs. SA1 (Phase I): Integrate hardware and software for whole-slide MCAM-3D capture: Ramona will complete development of an MCAM-3D device that digitizes whole slides (12 cm2 area, 50 m thick) at 0.8 and 2.6 m/pixel lateral and axial resolution within 1.5 minutes. 3D viewing software will enable real-time interaction with the multi-gigabyte recorded data volume, offering ~50X more measurements than current 2D whole-slide scanners. SA2 (Phase II): Evaluate MCAM-3D for telecytology and improve system specifications: In collaboration with 3 cytopathologists at the Duke University Medical Center, Ramona will test the MCAM-3D for remote rapid on-site evaluation (ROSE) of sample adequacy. ROSE is well-known to improve patient care by reducing repeat procedures. The objective of this aim is to show that the MCAM-3D can make ROSE easier, quicker and potentially more accurate. At the same time, Ramona will incorporate study findings to improve lateral/axial imaging resolution to 0.5 m/1 m and scanning speed to 30 sec. SA3 (Phase II): 3D whole-slide digitization and remote viewing for clinical applications: Ramona will improve the MCAM-3D's processing speeds to enable real-time remote viewing of 3D samples within the Duke University Medical Center. It will then work with cytopathologists to carefully assess its performance at telecytology-based diagnoses and archiving specimen material as it works towards a finalized product for sale 6 months after the conclusion of this project.